Archtop tail piece damage: Binding failure or?

[Kerry Krishna]

I  have been collecting 1930's Kay Kraft two points for close to a year now. Each one of the seven I have bought has had it's own problems. I started a Facebook Kay Kraft Guitar page if anyone is interested and already on Facebook. The guitar we have here today is a '31- 12 fret mahogany  6 string. All of these mahogany model and vintage ,if strung up to pitch these last 80 years, display this problem, along with a few other quite serious ones also. Frank et 'al, what do you think? Is this just a binding problem? Or if you can see the crack/distortion in the top right between the steel arms, is the endblock slowly failing? I have been trying to figure this out for a while, and am posting this to gain some adult supervision. Keep in mind also that all the 12 frets of this vintage are the exact same. Hide glue was used, if that makes any difference. Thanks Folks!

[Kerry Krishna]

Here are two more...

[Frank Ford]

Not a binding failure, but a design failure.  Look at the tiny support area for the arms of that tailpiece.  Good quality instruments have tailpieces with broad areas of contact.   A reasonable, easy and nonintrusive fix would be to use some metal angle shape between the tailpiece and the top, folded over the biding to provide necessary support.  It would look obvious of course, but could always be removed. Such a bent piece could extend down full length under the mounting "arms" of the tailpiece, and would provide really good support.

 

[Pierre-Antoine Roiron]

I don't think the endblock is giving up. Seems like a binding failure to me. You could give a try to a double-bass trick : inlay hard ebony instead of the soft plastic binding where the tailpiece is crushing it. Reglue the other plastic binding bits in place, and dovel with hardwood the screw holes, so that the tailpiece is firmly attached.

[Kerry Krishna]

Great idea  Pierre. Maybe this is the ticket...

[Tim Mace]

jus' guessing but looks like that end was banged pretty good w/strings tightened.Also over tightening was common around peeps w/no since of pitch control in those faded eras(earas).Or too heavy a string gauge...

[Kerry Krishna]

Tim, as I said above, all of the 20 or so guitars of this vintage are all the exact same, so I'm pretty sure it had nothing to do with the guitar getting banged. All of these axes, If  they were under string pressure for the full 80 years, this is what the binding will look like.

[Tim Mace]

otay

[Kerry Krishna]

Frank, I  am just realizing that I was not 100% clear on my original post. The 12 fret guitars from 1931 all have this problem, but the later 14 fret ones do not. Same tailpiece design, on the 14 fret, just two inches longer. That's why I am puzzled about this. It ONLY happened the one year. And I  totally agree that it IS poor design, but unless there is much more string pressure on the 12 fret, compared to the 14 fret, the idea does'nt really pan out. All the 14 fret guitars that have this same design

[Kerry Krishna]

Photos

[Mike Kolb]

I think FF nailed it.... there's too much concentrated pressure on the narrow arms of the tailpiece.

Now, why it shows up on the 12-fretters and not the 14-fretters remains a good question, but they seem to be exempt and that luckily cuts the casualty list by 50%.

After repairing the binding and whatever else needs fixing, there should be something installed to spread that pressure out. Then hang-around another 80 years to see if it works :)

[Kerry Krishna]

Pretty interesting problem eh  Mike?

 

[Tim Mace]

I'm w/you guys now!